requested_topping = 'mushrooms'
if requested_topping != 'achivs':
    print('hlow')

# 5.2.4 比较数字
anser = None
if anser != 42:
    print(anser)

# 5.2.5 检查多个条件
# 1．使用and检查多个条件
age_0 = 22
age_1 = 18
print(age_0>= 21 and age_1 <=18)
# 2．使用or检查多个条件
print(age_0>= 21 or age_1 <=18)

# 5.2.6 检查特定值是否包含在列表中
requested_topping = ['jtr', 'ers', 'lost']
print('jtr1' in requested_topping)

# 5.2.7 检查特定值是否不包含在列表中
if 'jtr123' not in requested_topping:
    print('aas')

# 5.2.8 布尔表达式
game_active = True
can_edit = False



age = 12
if age < 4:
    print(4)
elif age < 18:
    print(18)
else:
    print(age)